Minor bugfixes

app/main/initiative/_list.lua:
Replaced single by optional object mode

locale/translations.de.lua:
Consistent translation

app/main/initiative/_show.lua:
Added missing case "not approved" in voting info box

app/main/initiative/_show_voting.lua:
Added link to initiative

app/main/initiative/_show_voting.lua:
Added missing argument for link

app/main/member/show_tab.lua:
Added outgoing argument to show outgoing delegations correctly